Update tenant-allow-block-list.md

[msbemba]

Checked and found that the allow option does not exist anymore (apart from spoof). There is option only to block

reference articles https://docs.microsoft.com/en-us/microsoft-365/security/office-365-security/allow-block-email-spoof?view=o365-worldwide#create-block-sender-entries https://docs.microsoft.com/en-us/microsoft-365/security/office-365-security/allow-block-urls?view=o365-worldwide https://docs.microsoft.com/en-us/microsoft-365/security/office-365-security/allow-block-files?view=o365-worldwide

[msbemba]

@JohanFreelancer9 Please copy review

[chrisda]

Unassigning from me and assigning to @RatulaC

[yogkumgit]

@RatulaC Please merge this PR. Thanks

[chrisda]

Closing. I just completed massive updates to these topics, which nullifies the need for these changes.